逆作法超深基坑开挖过程风险监控分析及要点控制

Risk Monitoring Analysis and Key Point Control of Ultra-deep Foundation Pit Excavation Process with Top-down Construction Method

北京市某环路改造工程盾构施工准备标中间盾构工作井深度达43m,综合考虑基坑自身支护结构、基坑周边风险源等因素采用逆作法施工。作为北京地区超深基坑,且临近环路等重大风险源,其开挖过程中安全风险监控显得尤为重要。本文详细统计了基坑开挖过程不同阶段的变形数据,并结合数值模拟结果对不同阶段变形过程进行对比分析,总结风险管控要点,为下一步施工提供指导,实现了基坑开挖的支护动态化设计与施工,为类似工程提供参考。

The depth of the middle shield working shaft in the preparation standard of the one reconstruction Ring Road in Beijing is 43 m,and the top-down construction method was adopted to comprehensively consider factors such as the supporting structure of the foundation pit itself and the risk sources around the foundation pit.As an ultra-deep foundation pit in Beijing area,and close to the East Sixth Ring Road and other major risks,safety risk monitoring during the excavation process is particularly important.This article details the deformation data at different stages of the foundation pit excavation process and combines the results of numerical simulations.A comparative analysis of the deformation process at different stages is carried out to summarize the key points of risk management and control,provide guidance for the next step of construction,realize the dynamic analysis and adjustment of the foundation pit excavation support,and provide an important reference for the construction of similar projects in the future.